Table 1.

Summary of studies investigating body composition and insulin resistance in transgender individuals

Ref.	Country	Design	Time period	n	Average age (yr)	Number of controls	Methods	Lean mass	Fat mass	IR	WHR
Studies in Transgender men
Van Caenegem et al[41]	Belgium	Prospective controlled	12 mo	23	27 (9)	23 age-matched	DXA and pQCT	↑10.4%	↓9.7%		↔
Haraldsen et al[31]	Norway	Prospective controlled	3 mo, 12 mo	21	25.1 (4.8)	45, not age-matched	DXA	↑	↔
Cupisti et al[24]	Germany	Prospective controlled	12 mo	29	29.9 (18-40)	240 PCOS, age-matched	HOMA-IR			↔
Aranda et al[19]	Spain	Prospective	6 mo, 12 mo	20	27.1 (8.0)		DXA and HOMA-IR	↑5.8%	↓6.3%	↔	↑A:G ratio
Auer et al[21]	Germany	Prospective	13 mo	45	27.5 (1.3)		DXA and HOMA-IR	↑	↓	↓	↔
Klaver et al[32]	The Nether-lands and Belgium	Prospective	12 mo	162	24 (18-58)		DXA	↑10%	↓9%		↑
Gava et al[30]	Italy	Prospective	12 mo, 36 mo, 60 mo	50	30.1 (6.1)		DXA and HOMA-IR	↑	↔	↔	↔
Aranda et al[18]	Spain	Prospective	6 mo, 12 mo	12	27.1 (17-43)		HOMA-IR			↔	WC ↔
Auer et al[20]	Belgium and Norway	Prospective	12 mo	20	NR		DXA and HOMA-IR	↑	↔	↔	↔
Colizzi et al[23]	Italy	Prospective	12 mo, 24 mo	43	28.8 (5.6)		HOMA-IR			↔	WC ↑
Pelusi et al[37]	Italy	Prospective	30 wk, 54 wk	45	29.5		DXA and HOMA-IR	↑	↓	↔	↔
Wierckx et al[42]	Belgium	Prospective	12 mo	53	24.5 (7.0)		DXA	↑	↓		↑
Mueller et al[35]	Germany	Prospective	12 mo, 24 mo	45	NR		DXA	↑	↔
Yahyaoui et al[43]	United States	Prospective	12 mo, 24 mo	47	25.7 (6.0)		HOMA-IR			↓
Merigg-iola et al[34]	Italy	Prospective	12 mo	15	35.7 (5.0)		DXA and HOMA-IR	↑	↔	↔	↑ (NS)
Berra et al[22]	Italy	Prospective	6 mo	16	NR		BIA and HOMA	↑	↓	↔	WC ↔
Elbers et al[27]	The Nether-lands	Prospective	12 mo	17	23 (16-34)		MRI and EGC		↑ in VAT	↔
Elbers et al[25]	The Nether-lands	Prospective	4 mo, 12 mo	15	23 (16-34)		MRI and BIA		↓
Elbers et al[26]	The Nether-lands	Prospective	12 mo, 36 mo	10	24 (16-33)		MRI	↑ thigh muscle	↑ in VAT
Polderman et al[38]	The Nether-lands	Prospective	4 mo	13	23.1 (18-33)		BIA and EGC	↑		↑
Van Caenegem et al[39]	Belgium	Cross-sectional	10 yr on GAHT (3-28)	50	37 (8)	50 age-matched	DXA and pQCT	9% more	30% less		Larger
Studies in Transgender women
Haraldsen et al[31]	Norway	Prospective controlled	3 mo, 12 mo	12	29.3 (7.8)	77, not age-matched	DXA	↓	↑
Auer et al[21]	Germany	Prospective	12 mo	24	34.8(1.4)		DXA and HOMA-IR	↔	↑	↑	↓
Klaver et al[32]	The Nether-lands and Belgium	Prospective	12 mo	179	29 (18-66)		DXA	↓3%	↑28%		↓
Fighera et al[28]	Brazil	Prospective	31 mo	46	33.7 (10.3)		DXA	↓	↑
Aranda et al[18]	Spain	Prospective	6 mo, 12 mo	6	18.8 (16-21)		HOMA-IR			↔	WC ↑
Auer et al[20]	Belgium and Norway	Prospective	12 mo	20	NR		DXA and HOMA-IR	↓	↑	↑	↔
Gava et al[29]	Italy	Prospective	12 mo	40	31.2 (9.8)		DXA and HOMA-IR	↓ (NS)	↑	↔	↔
Colizzi et al[23]	Italy	Prospective	12 mo, 24 mo	79	30.2 (9.6)		HOMA-IR			↑	WC ↑
Van Caenegem et al[40]	Belgium	Prospective	12 months, 24 months	46	33 (12)	49 (not followed prospective-ly)	DXA and pQCT	↓	↑		↓
Wierckx et al[42]	Belgium	Prospective	12 mo	53	30.3 (14.0)		DXA	↓	↑		↓
Mueller et al[36]	Germany	Prospective	12 mo, 24 mo	84	NR		DXA	↓	↑
Yahyaoui et al[43]	United States	Prospective	12 mo, 24 mo	22	23.1 (9.4)		HOMA-IR			↔
Elbers et al[27]	The Nether-lands	Prospective	12 mo	20	26 (18-36)		MRI and EGC		↑ VAT	↑
Elbers et al[25]	The Nether-lands	Prospective	4 mo, 12 mo	17	26 (18-37)		MRI and BIA		↔
Polderm-an et al[38]	The Nether-lands	Prospective	4 mo	18	26.5 (18-36)		BIA and EGC	↓ (NS)		↑
Lapauw et al[33]	Belgium	Cross-sectional	8 yr on GAHT (4-20)	23	41 (7)	46, age-matched	DXA, pQCT	20% lower	30% higher

A:G ratio: Android-Gynoid ratio; BIA: Bioelectrical Impedance Analysis; DXA: Dual-energy X-ray Absorptiometry; ECG: Euglycaemic clamp; HOMA-IR: Homeostasis model assessment of Insulin Resistance; IR: Insulin resistance; MRI: Magnetic Resonance Imaging; NR: Not reported; NS: Not significant; pQCT: Peripheral Quantitative Computed Tomography: VAT: Visceral adipose tissue; WC: Waist circumference; WHR: Waist-hip ratio. Ages given as mean (SD or range).